Sheet-like Cellulose Nanocrystal-ZnO Nanohybrids as Multifunctional Reinforcing Agents in Biopolyester Composite Nanofibers with Ultrahigh UV-Shielding and Antibacterial Performances

Abstract

The uses of inorganic metal oxide and ZnO nanohybrids as UV absorbers have potential to increase the production of UVprotective textile, which will also overcome the drawbacks of organic molecules and prevent negative impacts on human health and environment. In this work, sheet-like cellulose nanocrystal-ZnO (CNC-ZnO) nanohybrid was successfully developed by one-step hydrothermal method. The obtained CNC-ZnO nanohybrids as UV absorber and antibacterial agents were introduced into biopolyester (poly(3-hydroxybutyrate-co-3-hydroxy valerate, PHBV) by using electrospinning process. The addition of sheet-like CNC-ZnO can greatly enhance PHBV thermal stability and crystallization ability. In addition, excellent antimicrobial ratios of Escherichia coli and Staphylococcus aureus and high absorbency of solution A (9.82 g/g) were obtained for the composite nanofibers with 5 wt % CNC-ZnO. Moreover, most of the UV irradiations were blocked out for both UVA (99.72%) and UVB (99. 95%) with high UPF value of 1674.9 in the resulting composite nanofibers with 9 wt % CNC-ZnO. This study provides a novel method to produce sheet-like CNC-ZnO with multifunctional properties and its nanocomposite for potential uses as wound dressings and other functional biomaterials.

Nanocellulose Hybrids with Metal Oxides Nanoparticles for Biomedical Applications

“…Owing to the electrostatic interactions between cellulose nanocrystals and zinc oxide, sheet-like CNC-ZnO nanohybrids were successfully developed by a one-step hydrothermal method [ 88 ]. CNCs were prepared by mixing microcrystalline cellulose (MCC) with an acid solution consisting of 90% citric acid and 10% HCl, at 80 °C for 6 h. The final CNC suspension (neutralized with NH 4 OH and washed with distilled water) was added in an aqueous solution of ZnCl 2 containing NaOH as precipitating agent and homogenized at room temperature.…”

“…In addition, FE-SEM images revealed that the morphology of CNC-ZnO nanohybrids varied from nanosheets to flower-like structures depending on the concentration of Zn 2+ ions. The insertion of CNC-ZnO into the PHBV matrix provided it a UV-blocking ability for both UVA (99.72%) and UVB (99.95%) and excellent antimicrobial activity against Escherichia coli and Staphylococcus aureus [ 88 ].…”

“… Schematic representation of the CNC-ZnO nanohybrids preparation procedure and the poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV)/CNC-ZnO electrospinning process [ 88 ]. …”

Electrospun Polyethylene Glycol/Polyvinyl Alcohol Composite Nanofibrous Membranes as Shape-Stabilized Solid–Solid Phase Change Materials

“…That was due to the introduce of PEG that would destroy the continuous phase structure of the PVA. Therefore, the addition of PEG was an unfavorable effect to the tensile properties of the composite fibers [22,46]. When the content of PEG as high as 70% (PEG/PVA = 7:3), the break tensile strength of the electrospun membranes still as high as 0.8 MPa.…”

Femtosecond Pulse Ablation Assisted Mg-ZnO Nanoparticles for UV-Only Emission

“…ZnO owes this popularity to its large bandgap, ease of doping [4] and its relatively large exciton binding energy, 60 meV, evident even at room temperature. While these features make the ZnO system an attractive choice for optoelectronics [5][6][7][8], they also render it an important candidate in photocatalytic, antibacterial and biomedical technologies [9][10][11]. The emission spectra of ZnO nanostructures are sensitive to their shape, size and defect content [8,[12][13][14].…”